This paper analyses three components of total cutting force and chip shape changes when finish turning 17-4 PH (precipitation hardening) stainless steel. A Finite Element Method (FEM) simulation of cutting forces was also performed using the Johnson–Cook constitutive model. The results were compared with those obtained from experimental studies. Variable feeds of 0.05–0.4 mm/rev and depth of cut of 0.2–1.2 mm with a cutting speed of 220 m/min were used. The studies were carried out under dry and wet cooling conditions and with the use of minimum quantity lubrication (MQL). This research was realized based on the Parameter Space Investigation (PSI) method. Statistical analysis of the obtained results was carried out using Statistica-13 software. It was found that the cutting force F_c and feed force F_f depend on the depth of cut and feed, and the passive force F_p depends mainly on the feed. Compared to dry cutting conditions, a reduction of 43% and 39% of the cutting force F_c was achieved for wet machining and MQL machining, respectively. Regardless of the cooling conditions, a favorable chip shape was registered for a_p = 1–1.1 mm and f = 0.25–0.3 mm/rev. Compared to the experimental studies, the FEM simulation showed differences of ~13% for the cutting force F_c and of ~36% for the feed force F_f.

Titanium alloys, particularly Ti-6Al-4V, are widely used in many industries due to their high strength, low density, and corrosion resistance. However, machining these materials is challenging due to high strength at elevated temperatures, low thermal conductivity, and high chemical reactivity. This study investigates Recurrence Plot (RP) and Recurrence Quantification Analysis (RQA) to analyze tool wear during the finish turning of Ti-6Al-4V. The tests were conducted under Minimum Quantity Lubrication (MQL). Three inserts (two coated, one uncoated) were tested, and tool life was evaluated based on material removal volume. The issue of tool exploitation and process reliability is crucial, as it directly impacts machining performance. Results show that the uncoated insert outperformed the coated ones. RQA parameters indicated a stable-to-unstable transition in coated inserts but not in the uncoated insert. This suggests that recurrence analysis can monitor cutting dynamics in coated insert machining, but further research is needed for uncoated tools. This paper’s novelty lies in applying RP and RQA to diagnose tool wear in titanium alloy machining under MQL conditions, a method not previously explored in this context.

Titanium alloys are included in the group of difficult-to-cut materials. The use of different methods to reduce the temperature of the machining zone is one of the factors influencing the performance of the machining. The most commonly used method is flood cooling. On the basis of recent...

This study combined simulation and experimental tests to analyse the cutting performance of three solid carbide end mills with distinct geometries during the milling of the 7075 aluminium alloy. For the tests, three uncoated end mills were employed, which differed in rake angle, clearance angle,...

This paper presents the experimental results of a study investigating the milling process of aluminium alloy EN AW-7075 T651. The main objective of the study was to establish the relationship between machining conditions, such as cutting parameters and cutting tool type, and selected machinability indicators, i.e. cutting force components and surface roughness parameters. The milling process was conducted using two different tools: a solid carbide cutter and a cutter with PCD (polycrystalline diamond) inserts. Obtained results showed that the use of the PCD tool led to a significant improvement of surface quality. In particular, the surface roughness parameter Ra was reduced, but changes are also visible for the other roughness parameters. Despite a similar trend of variations in surface roughness parameters observed for both tools, the values of these parameters obtained with the PCD tool were significantly lower. Similar values of the cutting force components were obtained with both cutting tools, these values being lower only in some cases for the carbide cutter. The effect of varying the cutting speed and feed per tooth on these indicators was also determined. The obtained results indicate that the selection of cutting parameters depends primarily on the expected results. Considering the surface roughness, it is better to use high cutting speeds, while in terms of cutting force, low speeds are more beneficial. In both cases, it is recommended to use the lowest possible feed.

The use of the minimum quantity lubrication (MQL) method during machining leads to the reduced consumption of cooling and lubricating liquids, thus contributing to sustainable machining. To improve the properties of liquids used under MQL conditions, they are enriched with various types of micro- and nanoparticles. The purpose of this study was to investigate the effect of the addition of graphite micropowder (GMP) on tool life, cutting force components, and selected surface roughness parameters during the finish turning of the Ti-6Al-4V titanium alloy under MQL conditions. The addition of 0.6 wt% of GMP to the base liquid in machining under MQL conditions leads to an extension of tool life by 7% and 96% compared to machining with a liquid without the addition of GMP and dry machining, respectively. Mathematical models of the cutting force components and surface roughness parameters were developed, taking into account the change in cutting speed and feed. It was found that the use of a liquid with the addition of GMP extends the range of cutting parameters for which the shape of chips obtained is acceptable in terms of work safety. The novelty of this study lies in the use of a cutting fluid composed of bis(2-ethylhexyl) adipate and diester, enriched with graphite micropowder, which has not been extensively investigated for machining titanium alloys under MQL conditions.